Seroprevalence of herpes simplex virus type 1 and type 2 - data from a hospital-based study in Varna, northeastern Bulgaria, 2019-2021.

The purpose of the current study was to describe the prevalence of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in northeastern Bulgaria. From January 2019 to December 2021, we tested 1493 samples for anti-HSV-1 IgG and 817 samples for anti-HSV-2 IgG antibodies in the Virology Laboratory, "St. Marina" University Hospital, Varna, Bulgaria. HSV-1 was considerably more widespread, with an overall seroprevalence of 73.3% (95% CI: 71.0-75.5%), than HSV-2 infection, which showed a seropositive rate of 10.0% (95% CI: 8.1-12.4%). Age was the most significant risk factor for both infections, while gender had no role in herpes simplex seropositivity.

Epidemiological study of Lyme disease in Bulgaria.

OBJECTIVES: Lyme disease (Lyme borreliosis) is a transmissible infection, common in the temperate climate zones. It is caused by a group of spirochetal bacteria known as Borrelia burgdorferi sensu lato complex. The aim of the present work was to investigate the incidence rate of borreliosis in different regions of Bulgaria and to identify possible risk factors for its occurrence. METHODS: National and regional borreliosis incidence rates for 2009-2018 were obtained from the public database of the National Centre of Public Health and Analyses. Their association with some socio-demographic variables and the geographic location (south or north) of the regions was tested with Spearman's correlation analysis and simple linear regression. RESULTS: The mean annual incidence for the last 10 years (2009-2018) in Bulgaria was 6.9 (range 4.1-11.6) cases per 100,000 inhabitants. We found that the Lyme disease was highly fluctuating at regional level with incidence rates varied from 0.3 to 30.9 per 100,000 inhabitants. Several regions showed significantly higher endemicity for the disease. Socio-demographic factors were not found to be important for Lyme disease frequency while the geographic location in the north part of the country was a significant risk factor for it. CONCLUSIONS: Lyme disease is a serious health risk in Bulgaria especially in its northern part - regions on the north are the most vulnerable to a higher incidence of the disease.

Seasonal influenza vaccination: knowledge, attitude and practice in Varna, Bulgaria.

BACKGROUND: Seasonal influenza vaccination is recommended for certain at-risk groups in Bulgaria, but vaccine coverage and the population's perception of vaccination are currently unknown. The objective of this study was to assess the level of seasonal influenza vaccination in Varna Region, Bulgaria. It also aimed to investigate the status of knowledge and the attitude towards the reliability, safety, and other aspects associated with the use of influenza vaccines. METHODS: A cross-sectional survey was conducted among 120 responders in Varna Region, Bulgaria. They completed a questionnaire assessing the practice, knowledge, and attitude towards seasonal influenza vaccination. RESULTS: Nearly 70% of all responders have never been vaccinated against seasonal influenza in their lives. The main reason indicated was a lack of confidence in the vaccine in general (53.7% of nonvaccinated responders). Individuals with insufficient knowledge, or with a negative perception, were more likely to not be vaccinated: being poorly informed and having a negative attitude towards influenza vaccination also decreased the chance of being vaccinated by 29% and 36%, respectively. CONCLUSIONS: This study indicates that efforts should be made towards achieving better understanding and knowledge of the vaccine's mechanism of prevention and effectiveness among the Bulgarian population.

Epidemiological Study of Hepatitis A Infection in Eastern Bulgaria.

BACKGROUND: Hepatitis A virus (HAV) infection is an acute, self-limited liver disease transmitted usually through the faecal-oral route via person-to-person contact. Bulgaria has intermediate HAV endemicity with higher susceptibility among adults and recurrent outbreaks. AIM: As HAV infection is strongly related to human movements and represents a significant risk to travelers and migrants, as well as to local population receiving these groups, we set out to analyze the epidemiological data on hepatitis A in five of the largest tourist border regions of Bulgaria located in its eastern part: Varna, Shumen, Dobrich, Burgas and Yambol. MATERIALS AND METHODS: We reviewed retrospectively all reported cases of acute hepatitis A in the eastern regions of Bulgaria over a 7-year period between 2008 and 2014. RESULTS: A total of 2879 newly infected patients were registered during the study period, the number varying widely: from 190 cases in 2014 to 923 in 2012. The average incidence of HAV was higher in the south-eastern regions than in the northeastern regions (55.30%000 vs 15.04%000 respectively, p < 0.0001). The most affected age group in all regions was the 5-9-year olds (p < 0.0001) and males were significantly more susceptible to HAV (p = 0.02). CONCLUSION: Hepatitis A is still a major public health problem in Bulgaria; there is a significant difference in the incidence of the disease between the regions in the south-east and those in the north-east and between the different age groups and sexes.

Seroprevalence of hepatitis B among pregnant women in Varna Region, Bulgaria.

The aim of the present study was to assess the prevalence of hepatitis B surface antigen among pregnant women in Varna Region, Bulgaria. During the period 2009-2013, an average prevalence of 2.26% (95%CI 1.75, 2.91) was measured in a total number of 2,700 samples. Analysis demonstrated that rural residence and minority ethnic origin are important risk factors for hepatitis B infection among pregnant women with hazard ratios of 2.40 (95%CI 1.46, 3.94), and 2.43 (95%CI 1.46, 4.05) when compared with urban residence and ethnic majority origin, respectively. J. Med. Virol. 88:2012-2015, 2016. © 2016 Wiley Periodicals, Inc.

Seroprevalence of Syphilis among Pregnant Women in the Varna Region (Bulgaria).

Syphilis is a sexually transmitted disease with continuously rising rates among European countries. The vertical (mother to child) transmission is an important way of dissemination, often leading to stillbirth and permanent impairment of the newborn. We present a retrospective cross-sectional analysis of 2702 pregnant women tested for syphilis seropositivity. During the study period (2009-2013) non-specific and specific treponemal antibodies were detected in 15 pregnant women (0.56% of sample size with 95% confidence interval (CI) 0.28-0.84). Our results showed a lack of correlation between syphilis seropositivity and age, ethnic origin, or pregnancy trimester of the mother. The only factor found to influence syphilis seropositivity was the mother's place of residence - rural inhabitants had significantly higher risk for syphilis infection when compared to urban inhabitants, with a seropositive proportion of 1.08% versus 0.36%, respectively.